does brand of fiberglass cloth make a difference?

[davisr]

I'm trying to get the best deal on fiberglass cloth (in the 6 oz. range) for several projects in which I plan to use West Systems epoxy. It seems there are three brands of cloth to choose from: West Systems Episize, Evercoat, and Composites One.

It appears that the best deal on West Systems Episize is at pbsboatstore.com, where at 10 yard roll of 60 inch cloth is $144.95. http://www.pbsboatstore.com/episize-glass-fabric.htm

When it comes to the Evercoat brand, Jamestown Distributors sells a 3 yard pack of 38 inch cloth for $25.11. This beats the West Marine price which is $14.99 for just 1 yard.

http://www.jamestowndistributors.co...19&familyName=Evercoat+Marine+Sea-Glass+Cloth

http://www.westmarine.com/1/1/12652-fiberglass-cloth-density-6-oz-60-w-bulk-from-evercoat.html

The Composites One brand, which in the boating world is sold by Defender, appears to be the most affordable. Unlike the other brands, at 6 oz, this brand is sold in a 7.5 oz size. Defender sells a 58 inch wide size for $9.99 yard.

http://www.defender.com/product.jsp?path=-1|10918|16458|311437&id=16940

Does anyone have any strong opinions about any of these brands. I want to get the best deal, but I also want a quality product.

Thanks for any suggestions,
Roscoe

 

[Emerald]

Give a shout to U.S Composites. No relationship, just a happy customer. Here's a page with some price on cloth. Knowledgeable folks to talk to also.

http://shopmaninc.com/cloth.html

 

[u079721]

I've never done any extensive glass work that needed more than a few yards, so I've always just bought the West System stock. But I can offer the cautionary advice that (duh!) all glass is not created equal. When I took the "Glue U" epoxy course from West Marine in Bay City one winter they mentioned that one of the important factors in glass quality can be the sizing used to extrude the glass fibers, and how well (if at all) that sizing is removed. If the sizing is not well removed, it can affect the quality of the bond to the fibers, sort of like residual mold release.

That's not to say that any particular brand of glass might not be good stuff, but I would consider the project before I bought any discount price glass. If for example I were glassing in a battery box, I would not shy away from the cheap stuff. If I were doing a hull repair, I would want to stick with stuff that is well known and that has a good rep.

Maybe ask a local glass repair place what they buy?

 

[rwthomas1]

I'll second the recommendation for US Composites. I built two hovercraft from scratch using their products pretty much exclusively. I like West System but think it overpriced. I have had good results with System Three and MAS epoxies, they are cheaper but IMHO the same quality as West.

http://shopmaninc.com/cloth.html
http://www.systemthree.com/
http://www.masepoxies.com/public/

RT

 

[bigd14]

<TABLE id=Table5 border=1 cellSpacing=1 cellPadding=1 width="100%"><TBODY><TR style="HEIGHT: 18px"><TD vAlign=top align=left>

[FONT=Comic Sans MS,Chicago,Sans-serif,cursive][SIZE=-1]Style 7533, 5.6 oz./yd.² X 60" Fiberglass Cloth, Plain Weave, Volan, Roll [/SIZE][/FONT]​

</TD><TD vAlign=top align=left>

[FONT=Comic Sans MS,Chicago,Sans-serif,cursive][SIZE=-1]$6.81[/SIZE][/FONT]​

</TD><TD vAlign=top align=left>

[FONT=Comic Sans MS,Chicago,Sans-serif,cursive][SIZE=-2]125yds[/SIZE][/FONT]​

</TD></TR></TBODY></TABLE>

I used www.fiberglasssupply.com and have been happy with the product (both this cloth and their 1708 biax).

Good luck.

Doug

 

[tenders]

From what I understand you have to be very careful in buying fiberglass mat and cloth because if you get the kind that doesn't have the sizing removed, epoxy will not adhere to it properly, but polyester resin will. So make sure whatever you buy is suitable for use with epoxy.

I find the West Marine stuff ridiculously overpriced and have never been disappointed with Defender or Jamestown products.

 

[davisr]

Thanks for all the sound advice. I just borrowed a book from a friend of mine on woodstrip kayak construction - not because I want to build a kayak, but because it contains information on the issue of epoxy and the proper use of cloth. Ted Moores, KayakCraft (WoodenBoat Publication, 2000), is a big fan of West System epoxy. In Chapter 9, "Fiberglassing the Hull," he writes: "It is important that the finish on the fiberglass cloth be compatible with the resin you are using. After the glass fibers have been woven into cloth, the cloth is fired to remove [emphasis added] all residual wax and oil and then finished with a coupling agent. The coupling agent is the interface between the glass fibers and the resin. Sticking well to both glass and resin, it keeps the bond from deteriorating. There are many different finishes available, but few are compatible with epoxy for our purposes. To be sure, buy your cloth from your epoxy dealer and ask if the finish is compatible with the epoxy."

I guess this corresponds to what several of you meant by the word "removed." So I guess the bottom line is that you must be careful with your choice of cloth when dealing with epoxy, whether it be West System, or another brand. Likewise, you can be a little more carefree in your choice of cloth when dealing with polyester resin.

I really like the prices on the websites you provided. West System, in comparision, is really pricey. Are there some out there who swear by West System?

Thanks,
Roscoe

 

[tenders]

I love West System epoxy and fillers because I know they're going to work with the excellent instructions that West provides on all sorts of projects, and all the places that sell it tend to move it reasonably quickly so I know what I buy off the shelf is pretty fresh.

I've used System Three and one or two other epoxy manufacturers over the years and they're fine, but West is much more readily available and the 5:1 resin:hardener ratio is easy to remember. There is nothing worse than being one shot short of the necessary resin to finish a project...and not being able to get the stuff.

I am NOT a fan of West System pumps and do not use them -- while they're OK for the first use, it seems that over time the hardener always siphons itself out of the pump and makes an ungodly mess. But other than that West stuff is good.

I don't buy West-branded cloth, mat, stir sticks, acid brushes or mixing cups.

 

[Loren Beach]

pump trivia

Regarding the problem with the spout dripping on the West System pumps...
I found a remedy for this many years ago. The problem is thermal expansion inside. Especially on warm days the resin (or hardener) expands and oozes out of the spout, slowly, and makes a little puddle. That's an expen$ive puddle over time.
When the current work is done I unscrew the cap/pump assembly a few turns, and that lets the pressure equalize inside the can. No drips.

When ready to express some product, I screw the cap back down first. Actually, having the cap on tight or loose seems to have no effect on operating the pump plunger.

Loren

 

[tenders]

Loren - thanks for the tip. I think trying that was how I discovered that when the hardener is exposed to air for a few months, it turns dark brown, which lightens to an odd red when mixed with the resin. It still works, but the color, plus the fact that I don't like to shuttle my epoxy kit between boat, boat locker, and home with unsealed epoxy components sloshing around in their cans, makes those pumps not worth the trouble.

Maybe if I had an entire "EpoxyWorks" in my basement like the Gougeon brothers, and slung gallons of epoxy a month, then this wouldn't be an issue....? I have always been impressed by the 55-gallon drum sizes they offer in their literature. Now that's some serious 'poxy.

 

[Loren Beach]

Loren - thanks for the tip. I think trying that was how I discovered that when the hardener is exposed to air for a few months, it turns dark brown, which lightens to an odd red when mixed with the resin. It still works, but the color, plus the fact that I don't like to shuttle my epoxy kit between boat, boat locker, and home with unsealed epoxy components sloshing around in their cans, makes those pumps not worth the trouble.

So true about the hardener. The can I am about finished with is a brown color and the mix is a very light tan. Per what I read, this has no effect on the chemistry tho. This is a two year old can.
I just built a replacement honeycomb shelf for the laz. The new one weighs about 6# and replaced a factory piece of 3/4" ply that weighed about 16#.
I was wrapping some light cloth around the exposed Hexel edges and also gluing on a higher fiddle rail than was on the original one.

"All good clean fun!"

Loren
:nerd:

 

[davisr]

Tenders,

You said you use West System epoxy and hardener, but get your cloth from Defender or Jamestown. Which brand of cloth at Defender or Jamestown do you find works the best with West?

Thanks,
Roscoe

 

[tenders]

To be honest, I just don't know...I bought a bedsheet's worth from Jamestown a few years ago and have been gradually cutting it down to the point at which I have a few pillowcases' left these days.

 

[Dan Morehouse]

I started using WEST resin thirty years ago when I started building a cold molded Roberts 22. I don't remember where I got what little fiberglass I used on that boat, but for recent projects I've ordered it from Defender. This is the first discussion I've ever heard about compatibility issues between epoxy and various brands of fiberglass. Feeling a little dumb about that, but hey, it just goes to demonstrate the value of this site.

Right now I'm at the end of a can of WEST fast hardener that is probably five years old or more. It's a dark red color, but it appears to still be good...I built a plywood & fiberglass fuel tank with it.

What does bother me about WEST resin is the amine blush. I suspect it to be the cause of a couple of coating failures I've seen. But I've never had any fiberglass/epoxy application fail, so maybe all the cloth I've gotten through Defender I just got lucky with. Regardless, I'm about to try one of the epoxy brands that advertise no amine blush...and start paying closer attention to the product descriptions before buying the next batch of cloth.

Dan Morehouse
1981 E-38 "Next Exit"

 

[bigd14]

I have been using Raka epoxy for the past year. Almost no amine blush (although I still wash with water and a scotch-brite pad), and so far it seems solid (I can't speak for its ultimate longevity). I like the fact that I can mix the slow and fast hardeners to control cure time, which I can't do with West. Best of all its about 1/2 the price of West, even with shipping from Florida. Raka also has started selling fiberglass cloth and they specifically mention the compatibility issue. They seem pretty competitive on price of FG too.

The usual disclaimer that I have no financial interest (except saving 50% on epoxy) in Raka...

 

[tenders]

Raka, that's good to know. I've seen the ads for it in Good Old Boat magazine.

> I like the fact that I can mix the slow and fast hardeners to control cure time, which I can't do with West.

I'm pretty sure you can do that with West too, although I've never tried.

Fast cure epoxy cooks off on me too soon about 35% of the time. I almost never use it, and just plan my project execution to fit around slow cure.

 

[Dan Morehouse]

My understanding of WEST resin is that they specifically do not recommend mixing two hardeners. Being accustomed to WEST, I was surprised the first time I ran across an epoxy that allowed it. I had been under the impression that single hardeners was a feature common to all epoxy.

Dan Morehouse
1981 E-38 "Next Exit"

 

[tenders]

My understanding of WEST resin is that they specifically do not recommend mixing two hardeners. Being accustomed to WEST, I was surprised the first time I ran across an epoxy that allowed it. I had been under the impression that single hardeners was a feature common to all epoxy.

Dan Morehouse
1981 E-38 "Next Exit"

I do believe you can combine many hardeners to change the cure time, as long as you don't change the overall 5:1 ratio of resin:hardener. (With polyester resin, you can fiddle a little with the hardener ratio to twiddle the cure time.)

From about halfway down the page:
http://www.boater.com/repinfo/westsys/west1.html

"205(fast) and 206 Slow Hardener may also be mixed to provide a custom blend with an intermediate open and overall cure time. It is critical, however, that the proper 5 part resin to 1 part hardener ratio is maintained."

This isn't directly from West per se, it's been cribbed and slightly modified from instructions from a West subsidiary called Pro-Set (page 4).
http://www.prosetepoxy.com/PDF/1 Laminating Epoxy/02_Handling_Guide.pdf

My guess is that West doesn't put this into the West System literature because they don't want to confuse novices about the all-important 5:1 ratio, whereas Pro-Set is targeted towards more expert industrial users.

 

[bigd14]

Agreed that you can mix West hardeners, the problem I had IIRC is that the 209 extra slow is a 3:1, and I don't like to do that much math when mixing up a simple pot of epoxy... I like the 2:1 simplicity of Raka, System 3, etc. You want to speed it up a little, just throw in a shot of the fast hardener. I guess you can do the same with the West, it just seems easier with the 2:1 ratio's.

I had a major problem when I tried to use the West pump system at 5:1. Since I was so used to using the 2:1 pump system, I assumed since it was 5:1 that I needed 5 pumps of resin to one pump of hardener. Of course it didn't cure right, since I only needed one pump of each (they are metered differently). Apparently the idiot-proof system didn't anticipate that kind of idiot

 

[tenders]

They didn't say you could mix the 209 hardener with other stuff...just the 205 and 206, which are both 5:1 ratio hardeners.

I made the same mistake with the West System pumps. But only once, though.